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PERTUSSIS Control Guidelines for Public Health Units
1. Summary
Case and contact management is challenging for pertussis. The evidence base is limited and the
epidemiological behaviour of Bordetella pertussis is not well understood. This partly explains
why pertussis is a poorly controlled bacterial vaccine-preventable disease.
Public health priority
High. Begin public health follow up as soon as possible, generally within 1 working day (see
Response Times in Section 9). The objective of public health follow up of pertussis cases is to
prevent disease in infants <6 months of age with particular focus on exposures in household, child
care and health care settings. Therefore highest priority should generally be given to cases who are
nucleic acid test (NAT) or culture confirmed and:
If the case is a child under 5 years of age, follow up the younger cases (<2 years)
before the older cases
other age groups where cases are already known to have close contacts that include
infants <6 months of age
are women known to be in the last month of pregnancy
No action is required for cases notified >21 days after the onset of paroxysmal cough (if the onset is
known) or >28 days after the onset of any cough unless they are reported to be part of a cluster.
Case management It is the responsibility of the treating doctor to treat infectious cases and consider the need for
further public health action for any high risk contacts. For cases considered high public health
priority (see above) contact the treating doctor or case to identify any contacts that are infants
<6 months of age or people who may transmit pertussis to these infants, and advise on
management of case and contacts as necessary. For other cases, an advisory letter may be sent to
the treating doctor, as required.
Contact management For cases considered high public health priority, counsel their close contacts and facilitate antibiotic
prophylaxis where necessary. Recommend that contacts’ immunisations be updated if
appropriate.
2. The disease
Infectious agents
The bacillus Bordetella pertussis (B. pertussis)
Reservoir
Humans are the only reservoir for B. pertussis. Adults and adolescents are often an important
source of infection for infants.1
Mode of transmission Pertussis is mainly transmitted by large droplet infection or direct contact with discharges from
respiratory mucous membranes of infectious people. Indirect spread via contaminated objects
occurs rarely.2 There is some experimental evidence which supports airborne transmission over
distances greater than one metre.3
Clinical presentation and outcome
Pertussis is a prolonged coughing illness with clinical manifestations that vary by age. An initial
catarrhal phase is characterised by the insidious onset of runny nose, sneezing, absent or low-
grade fever, and a mild occasional cough. The cough gradually becomes paroxysmal (after 1–2
weeks), and may end in vomiting, cyanosis and/or a characteristic high-pitched inspiratory
‘whoop’. Paroxysms may recur with subsequent respiratory illnesses for many months after the
onset of pertussis.1 Fever is generally minimal throughout the course of the illness and sub-
clinical infections may occur.1
Infants are less likely to have the inspiratory whoop and a significant
catarrhal stage and are more likely to present with gagging, gasping, cyanosis, apnoea or non-
specific signs such as poor feeding or seizures.4Adults and children partially protected by
vaccination can present with illness ranging from a mild cough illness to classic pertussis, though
this may be without the inspiratory whoop. In adults, post-tussive vomiting (when present) is
strongly suggestive of pertussis.4
The most common complication is pneumonia caused either
by B. pertussis infection itself, or co-infection with viral respiratory pathogens such as respiratory
syncytial virus (RSV).4 Encephalopathy is a rare complication.
4
Incubation period
The incubation period ranges from 4-21 days, usually 7 to 10 days.1
Infectious period Cases are infectious from the onset of catarrhal symptoms. Communicability gradually decreases
and is negligible 3 weeks after onset of cough. Secondary attack rates of 80% among
susceptible household contacts have been reported.1 For public health purposes, a case is
considered non-infectious (even if the PCR result is still positive) at whichever time is the earlier of:
21 days after the onset of any cough, or
14 days after onset of paroxysmal cough (if the onset is known), or
when they have completed 5 days of a course of an appropriate antibiotic.
Persons at increased risk of disease Infants under 6 months of age account for the vast majority of pertussis hospitalisations and
deaths; Australian data for 2009-2010 indicate a case fatality rate of less than 0.5% in infants too
young to be protected by vaccine.5, 6
Disease occurrence and public health significance Globally, pertussis remains a major health problem despite widespread vaccination programs. In
2009, 195 000 deaths were estimated from the disease, mostly in developing countries.7 In
Australia, pertussis is the most common acute vaccine preventable disease with epidemics
occurring approximately every 3-4 years and the timing of epidemic activity varying across
jurisdictions.8 It has only relatively recently been widely recognised as a common disease of
older children and adults.
3. Routine prevention activities Apart from direct case and contact management of pertussis, the following activities are routine
prevention activities at the population level.
Vaccination Pertussis immunisation is recommended for all Australian children with the first dose of pertussis-
containing vaccine given from 6 to 8 weeks of age9, followed by doses at 4 and 6 months, a booster
from 3.5-4 years of age10
and a further booster at 12-17 years of age. Lower- dose dTpa vaccines
suitable for use in adolescents and adults have been available since 2001. Since 2003, dTpa vaccine
has been recommended for healthcare workers and people working or living with infants, including
parents, grandparents, those planning pregnancy and childcare workers who have not previously
had a dose of the acellular vaccine. Immunity following vaccination begins to wane after as little as 4-
5 years. 11
Increase awareness Amongst the general public, it is important to raise awareness of:
early diagnosis and treatment of cases, by encouraging people with coughing illnesses to seek early
medical attention. This will facilitate timely treatment of pertussis cases (to reduce infectiousness)
and follow up of high risk contacts.
respiratory hygiene around babies, by encouraging people with coughing illnesses to
avoid contact with infants <6 months of age until a diagnosis is made and they are no
longer infectious.
Amongst general practitioners and other clinicians, it is important to promote ongoing clinical
education about pertussis that outlines appropriate diagnosis, treatment and the identification
and management of contacts.
4. Surveillance objective The objective of surveillance for pertussis is:
To monitor and analyse the epidemiology of the disease, including the impact of
immunisation, and to report on findings to inform effective and efficient prevention
strategies.
The objective of public health follow up of pertussis cases is:
To prevent disease in infants <6 months of age with particular focus on exposure in
household, childcare and healthcare settings
5. Data management Within 3 working days of notification, enter confirmed and probable cases onto the jurisdictional
notifiable diseases database. As soon as practicable, check and enter vaccination details for cases
under 5 years of age.
6. Communications Within 1 working day of becoming aware of a death from pertussis, notify the
state/territory Communicable Diseases Branch of the case’s age, sex, date of onset,
vaccination history, laboratory status, likely source of infection and follow up action taken.
The state/territory Communicable Diseases Branch should notify the case details to the CDNA
secretariat and update the ‘died’ field in the national notifiable diseases database.
The state/territory Communicable Diseases Branch should also be notified of significant pertussis
exposures in healthcare settings.
7. Case definition
Confirmed case
A confirmed case requires either:
1. Laboratory definitive evidence, OR
2. Laboratory suggestive evidence AND clinical evidence
Probable case
A probable case requires clinical evidence AND epidemiological evidence
Laboratory definitive evidence
1. Isolation of Bordetella pertussis , OR
2. Detection of B. pertussis by nucleic acid testing, OR
3. Seroconversion in paired sera for B.pertussis using whole cell or specific B.pertussis antigens (s) in the abscence
of recent pertussis vaccination.
Laboratory suggestive evidence
In the absence of recent vaccination
1. Significant change (increase or decrease) in antibody level (IgG, IgA) to B.pertussis whole cell
or B.pertussis specific antigen (s), OR
2. Single high IgG and/or IgA titre to Pertussis Toxin (PT), OR
3. Single high IgA to Whole Cell B. pertussis antigen.
Clinical evidence
1. A coughing illness lasting two or more weeks, OR
2. Paroxysms of coughing OR inspiratory whoop OR post-tussive vomiting.
Epidemiological evidence
An epidemiological link is established when there is:
1. Contact between two people involving a plausible mode of transmission at a time when:
1. one of them is likely to be infectious (from the catarrhal stage, approximately one week before, to three
weeks after onset of cough) AND
2. the other has an illness which starts within 6 to 20 days after this contact AND
2. At least one case in the chain of epidemiologically linked cases (which may involve many cases) is a confirmed
case with at least laboratory suggestive evidence.
8. Laboratory testing
Testing guidelines Routine testing of patients is at the discretion of the treating doctor. Public health personnel should
encourage testing to confirm any probable cases where contacts <6 months of age have been reported.
Laboratory testing of asymptomatic contacts should be discouraged.
With increasing availability, nucleic acid testing (NAT) should be considered the diagnostic
method of choice, unless the presentation is delayed until after 4 weeks from any cough
onset, or more than 3 weeks after commencement of paroxysmal cough, after which time
serological testing may be more useful for diagnosis.
Nucleic acid testing (NAT)
Nucleic acid testing (NAT) (also known by the proprietary name of PCR) has largely replaced culture
for the diagnosis of pertussis. NAT is more sensitive than culture and has optimal sensitivity during the
first 3 weeks of cough. After the fourth week of cough, sensitivity declines as the amount of bacterial
DNA in the nasopharynx diminishes.12
NAT can be positive for 5 weeks or longer; refer to Section 2 for guidance on the infectious period for
public health purposes.
NAT testing after 5 days of appropriate antibiotics is unlikely to be of benefit and is generally not
recommended.12
Nasopharyngeal aspirates or nasopharyngeal swabs with Dacron™ or rayon tipped swabs are
optimal and calcium alginate swabs should not be used. Throat swabs may also be used, although
they suffer from lower sensitivity. Swabs for NAT should be sent to the laboratory dry – not in
transport medium.
Further information including technique for collection of nasopharyngeal swab or aspirate can be found
at: http://www.cdc.gov/pertussis/clinical/diagnostic- testing/specimen-collection.html
Culture
The sensitivity of nasopharyngeal culture decreases rapidly after cough onset and is highly dependent
on specimen quality. Cultures are rarely positive after 2 weeks from the onset of the catarrhal stage of
the illness, or one week of paroxysmal cough, or for more than a few days after starting antibiotics.
If it is proposed to collect samples for culture of B. pertussis, the laboratory should be contacted
beforehand to enable swabs and culture media to be processed promptly.
Nasopharyngeal (not throat) cultures should be collected either by aspiration or with a flexible,
deep nasal swab. The swab should be inoculated directly onto special pertussis culture medium or
into transport medium, or both, according to the laboratory's specific instructions. The technique
is illustrated at http://www.cdc.gov/pertussis/clinical/diagnostic-testing/specimen-collection.html
Cultures may take as long as 2 weeks to be finalised, so results may not be clinically useful.
Serology
Although serological testing of pertussis has not been standardised, it was the predominant
diagnostic test until recently. Bordetella-specific IgA directed against whole-cell lysate has
been the most widely used test, particularly in adults and adolescents who present late in the
course of their illness, when both culture and NAT are likely to be negative. The serological
assays in use are, however, changing, with increasing use of purified antigens such as
pertussis toxin (PT) alone or in combination with filamentous haemagglutinin (FHA).
International standards for anti-PT and anti- FHA IgG and IgA have become available and
should allow for greater standardisation of assays in the future.
The sensitivity and specificity of serology is low. Serology may be useful if a clinically
compatible illness has been present for more than two weeks, but is not recommended in
children <2 years old as they are less likely to develop IgA antibodies and because phlebotomy
can be difficult for inexperienced venepuncturists.
Depending on which antigens are used in the assay, a positive Bordetella serological result may also
occur in parapertussis.
IgA and IgG may be elevated for an unknown period (reported as 1 year13
but may be as long as 2
years) in an adult or adolescent after vaccination, therefore caution should be taken in interpreting
serological results in a recently vaccinated person.
Bordetella-specific IgG and IgA rise during acute infection. If only a convalescent sample is
available the current suggestive criteria for recent infection in the absence of recent
vaccination include an elevated IgA antibody level to whole-cell B. pertussis or an elevated
IgG and/or IgA to pertussis toxin or other combination antigens. Commercial and in-house
validated assays utilising PT with or without FHA are now being introduced.
Bordetella IgM serology is available using commercial kits, but is currently not considered sufficiently
sensitive and specific for guiding public health decisions. An IgM response may follow infection in
young children in whom the IgA response is not yet mature.
For further information on laboratory testing refer to the Public Health Laboratory Network
(PHLN) laboratory case definitions website:
www.health.gov.au/internet/main/publishing.nsf/Content/Laboratory+case+definitions-1
9. Case management
Response times Begin the follow up within 1 working day of notification of high priority cases who are
NAT/culture confirmed, and more likely to be in contact with infants <6 months of age. The
principles for prioritising the workload among NAT/culture confirmed high priority cases are:
If the case is a child <5 years, follow up the younger cases (<2 years) before the older
cases
Follow up any case in a woman known to be in the last month of pregnancy
Follow up where the case is already known to be in contact with infants <6 months of age or
women in the last month of pregnancy
Follow up where the case is known to attend or work in a setting where there is likely to be
contact with infants <6 months of age or women in the last month of pregnancy (e.g.
certain childcare and healthcare settings)
Active public health action (e.g. exclusion, antibiotic use) is not required for cases notified >21
days after date of onset of paroxysmal cough (if the onset is known) or >28 days after the onset of
any cough—unless they are reported to be part of a cluster—as they are unlikely to be infectious.
Response procedure
Case investigation
For cases given priority as outlined above: Response will usually be carried out in collaboration with the treating doctor.
Public health personnel should:
Provide advice on case and contact management. The Public Health Unit may send a letter
and fact sheet (see example fact sheet, Appendix 1) to the treating doctor recommending
case and contact management
Investigate the case using a pertussis case investigation form (see example form, o Appendi
x 2)
For cases under 5 years of age, check and record primary vaccination status (including source
of verification)
For any other cases meeting the current case definition:
Public health personnel may:
Offer, as resources permit, to assist the treating doctor with cases when either high risk
contacts or clusters are identified by the treating doctor.
Exposure Investigation Where feasible for cases given priority, investigate the possible source of exposure-contact with a
confirmed or suspected case/s.
Case treatment Antibiotics given early in the catarrhal stage may ameliorate the disease but may have little effect
on symptoms if given later.14
Importantly, antibiotics reduce the period of communicability15
and should be initiated as soon as possible. If treatment starts any later than
14 days from onset of any cough, by the time 5 days of treatment are completed, the case is
already close to the end of their infectious period (21 days). Treatment is the responsibility of the
attending doctor. However, it should be noted that azithromycin, especially the syrup form, may be
difficult and/or expensive to obtain and that specific advice may be required. For recommended
treatment see the latest edition of Therapeutic Guidelines: Antibiotic.16
In 2014 the
recommendations were updated and are outlined in Table 1:
Table 1. Recommended antibiotic treatment and post exposure prophylaxis for
pertussis by age group
Age Group Macrolides Non-macrolide
alternative
Azithromycin (oral) Clarithromycin (oral) Trimethoprim +
Sulfamethoxazole (oral)
<1 month 10mg/kg daily for 5
days
7.5mg/kg twice a day
for 7 days (up to
500mg)
not recommended
1-5 months 10mg/kg daily for 5
days
7.5mg/kg twice a day
for 7 days (up to
500mg)
Child ≥2months
4+20mg/kg (up to
160+800mg) twice a
day for 7 days
Infants ≥6 months and
children 10mg/kg (up to
500mg) on Day 1,
followed by 5mg/kg
(up to 250mg) on
Days 2-5
7.5mg/kg twice a day
for 7 days (up to
500mg)
4+20mg/kg (up to
160+800mg) twice a
day for 7 days
Adults 500mg on Day 1
followed by 250mg
daily on Days 2-5
500mg twice a day for
7 days
160+800mg twice a
day for 7 days
Pregnancy Pregnant women with onset of pertussis or exposure within a month of
expected delivery should receive antibiotic therapy. It is the responsibility of
the treating doctor to select the most appropriate antibiotic. Azithromycin is
Category B1 and clarithromycin is a Category B3 antibiotic.16
Therapeutic Guidelines: Antibiotic notes there is currently no clinical evidence to recommend the
use of roxithromycin for the management of pertussis. In vitro evidence indicates it is relatively
ineffective. 17
Education The case or relevant care-giver should be advised about the nature of the infection and the mode of
transmission. The fact sheet is useful for this purpose (see Appendix 1). Cases should be advised
to avoid contact with infants and women in the last month of pregnancy.
Isolation and restriction Exclusion from work, school, preschool, and child care, and restricted attendance from other
settings, especially where there are infants, should be recommended for cases until they are no
longer infectious until:
21 days after the onset of any cough, or
14 days after the onset of paroxysmal cough (if the onset is known) , or
they have completed 5 days of a course of an appropriate antibiotic.
In hospital settings, infectious cases should be managed with droplet precautions and
accommodated in a single room.18
Active case finding None routinely required, except in special situations (see Section 12 Case in a healthcare worker in
a maternity ward or newborn nursery).
10. Control of environment Not required.
11. Contact management
Identification of contacts The aim of identifying contacts is to:
Alert them to the possibility that they could develop disease, and
Recommend antibiotic prophylaxis for the subset who are infants <6 months of age or
people who may transmit pertussis to these infants.
Direct contact with respiratory droplets from the case is likely to pose a significant risk of
transmitting infection. 14
Contact definition In general terms, close contacts are people with face-to-face exposure (within 1 metre) to an
infectious case,14
for a single period of at least one hour (based on expert opinion). In the absence of
evidence concerning the minimum duration of exposure required to lead to infections in neonates, a
neonate exposed to an infectious case for less than one hour may warrant being considered a close
contact. In addition, close contacts are usually considered to include family and household members
and, in other settings, people who have stayed overnight in the same room as the case.*
All close
contacts or their carers should receive information about pertussis symptoms (e.g. fact sheet).
*In non-household settings, the size of the room and degree of separation of the case from others should be
considered when close contacts are being identified.
In addition, a subset of close contacts are considered high-risk contacts because of the severity of
disease or the likelihood of transmitting infection to those at risk of severe disease and are
recommended antibiotic prophylaxis. For the purposes of this guideline, high-risk contacts are
infants <6 months of age and people who may transmit pertussis to them.
In the event of exposure in the household setting, high-risk contacts include:
expectant parents (or carers) in the last month of pregnancy
all household members where there is an infant <6 months present.
In any setting, close contacts of a case who are considered high-risk contacts include:
healthcare staff working in a maternity ward or newborn nursery (where women in the
last month of pregnancy or infants <6 months are present)
childcare staff who look after infants aged <6 months
children who have close contact in child care with children <6 months of age
women in the last month of pregnancy.
Management of immunodeficient contacts should be made on a case by case basis.
Prophylaxis
Passive immunisation Normal human immunoglobulin (NHIG) is not effective against pertussis. There is efficient
transfer of protective maternal antibodies across the placenta with a half life of 6 weeks and
disappearance by 4 months.19
As pertussis antibodies wane over several years, there will be
little humoral antibody protection for the infant unless the mother has been vaccinated or
infected shortly before or during pregnancy.19
Active immunisation Not applicable in the management of defined contacts. However immunisation should be
promoted according to NHMRC recommendations.
Antibiotic prophylaxis There is little evidence that antibiotic prophylaxis reduces secondary transmission outside of the
household setting.15, 20
The recommended antibiotics may have associated side effects (especially
gastrointestinal) that reduce compliance. Therefore antibiotic prophylaxis should be limited to
contacts that include infants <6months of age or people who may transmit pertussis to these infants
(high-risk contacts). Antibiotic prophylaxis is only useful if given as soon as
possible after first contact with an infectious index case 4, 14 Based on the preceding statements
and considering the decline in infectiousness during the infectious period, the timeline for providing
antibiotic prophylaxis to high-risk contacts should be within 14 days of first contact with an
infectious case and prophylaxis is recommended in the settings outlined in Table 2. Regimens for
antibiotic prophylaxis are the same as for treatment of cases–See Table 1 under Section 9 Case
Management.
Due to lack of evidence of effectiveness from these settings, antibiotic prophylaxis is not
considered valuable in other settings such as primary schools, high schools, tertiary institutions
and work places. If there are prolonged or multiple chains of transmission, the benefit of antibiotic
prophylaxis is likely to be minimal.21
Circumstances in which further contact occurs with an
index case satisfying the recommendations for antibiotic prophylaxis, should be
assessed to determine the risk of severe disease in contact/s and the benefit of repeat antibiotic
prophylaxis.
Use of Table 2:
The table does not cover all possible scenarios; other settings or exposures of shorter duration
where high-risk individuals have been exposed may warrant consideration for prophylaxis.
Presumptions and notes: Transmission is by respiratory droplets requiring close ‘household-type’ contact 1 Transmission is usually considered to require exposure within 1 metre for a single period of
1 hour. There is no evidence to guide decisions in relation to repeated shorter exposures
over a period of time with a cumulative total greater than one hour.
While antibodies to pertussis begin to wane within a year after vaccination in adults, they
remain above pre-vaccination levels for 10 years. 12
The 10th
edition of the Australian Immunisation Handbook recommends that no further doses of dTpa vaccine be given
routinely until 10 years after the first dose.6
Table 2. Recommendations for the management of contacts in various settings
Setting Provide advice
A,B Antibiotics
C Exclusion
D of non or incompletely
vaccinatedE people
Household Where household
contacts include an
incompletely vaccinated
child <6 months or
woman in the last month
of pregnancy
Household All household members,
regardless of vaccination
statusF
Not applicable
All other households Household Nil Not applicable
Child careG sporadic
case
Where there is an
incompletely vaccinated
child <6 months in
room (who is not the
case)
All staff and
parents
All children in room with
<3 doses of vaccine
Children: exclude for 5 days while on antibiotics
or 14 days (from first exposure to infectious
case) if they do not take antibiotics
Staff who have not had a
pertussis-containing
vaccine in last 10 yearsH
Staff: not excluded while taking 5 days of
antibiotics or recommend exclusion for 14 days
(from first exposure to infectious case) if they do
not take antibiotics
Where all children are All staff and Children: Nil Children: not excluded if they remain well
A These contacts should be alerted to the possibility that they could develop disease and to seek early medical assessment if they develop symptoms consistent with
pertussis. B Recommend vaccination to contacts, health care workers, and those who work with children who are incompletely vaccinated as they are likely to benefit in the
future if vaccinated. C Antibiotic prophylaxis is recommended for these contacts of pertussis cases, and should be given within 14 days of first exposure to an infectious case.
Regimens for antibiotic prophylaxis are the same as for treatment of cases. See Table 1 under Section 9 Case Management. D Any contacts that develop symptoms should, where possible, be excluded (immediately) from childcare, preschool, school, health care and workplace settings and seek
early medical assessment. E In the childcare setting, any child that has received <3 doses of vaccine is considered incompletely vaccinated F Choice of an appropriate antibiotic for use in pregnancy is the responsibility of the treating doctor. See Table 1 under Section 9 Case Management G Childcare settings include long day care, family day care or settings where children aged 4 years or less are in care before they start their first year in a school setting
(this can be called preschool or kindergarten in certain jurisdictions). See also Section 12 ‘Special situations: Cases among children in child care’. H Staff are regarded as vaccinated if they have had a pertussis-containing vaccine in the last 10 years
Setting Provide adviceA,B
AntibioticsC
ExclusionD
of non or incompletely
vaccinatedE people
≥6 months parents Staff: Nil Staff: not excluded if they remain well
Child care with 2 or
more cases in the
same room within a
single incubation
period I
Where there is an
incompletely vaccinated
child <6 months in
room (who is not the
case)
All staff and
parents
All children in the room
regardless of vaccination
status
Children: exclude for 5 days while on antibiotics
or 14 days (from first exposure to infectious
case) if they do not take antibiotics
All staff in the room
regardless of vaccination
status
Staff: not excluded while taking 5 days of
antibiotics or recommend exclusion for 14 days
(from first exposure to infectious case) if they do
not take antibiotics
Where all children are
≥6 months
All staff and
parents
All children in room with
<3 doses of vaccine
Children: exclude for 5 days while on antibiotics
or 14 days (from first exposure to infectious
case) if they do not take antibiotics
Staff who have not had a pertussis containing
vaccine in last 10 years8
Staff: not excluded while taking 5 days of
antibiotics or recommend exclusion for 14 days
(from first exposure to infectious case) if they do
not take antibiotics
Healthcare settings
where infants <6
months or women in
their last month of
pregnancy are
Case is staff member of
unit / ward or an
infectious patient who
has not been
appropriately isolated
All staff and
parents
Infants <6 months
exposed to the case
within 1 metre for >1
hourK
Not applicable
I See Section 12 Outbreaks. Due to the variety of childcare settings where two or more cases may be epidemiologically linked and the absence of strong
evidence for the effectiveness of antibiotic prophylaxis in these settings, a case by case assessment will usually be required to determine the appropriate
response. K In the absence of evidence concerning the minimum duration of exposure required for a neonate to be infected, a neonate exposed to an infectious case for
less than one hour may warrant being considered a close contact and receiving antibiotic prophylaxis.
Setting Provide adviceA,B
AntibioticsC
ExclusionD
of non or incompletely
vaccinatedE people
present (including
neonatal unit,
maternity ward)J
Parents or carers of
infants <6
months/women in last
month of pregnancy6
exposed to the case
within 1 metre for >1
hour
Not applicable
All staff exposed within
1 metre for >1 hour in the
unit who–in the next
3 weeks–are to care for
neonates or women in
the last month of
pregnancy regardless of
vaccination status
Staff: need only be excluded (immediately) if
they become symptomatic and are to be
excluded whilst considered infectious.
In situations in which asymptomatic staff
contacts have been recommended and refused
antibiotics (e.g. an outbreak) recommend
exclusion OR restrict from working with infants
<6 months and women in the last month of
pregnancy (for 14 days from first exposure to the
infectious case)
J See also ‘Special situations: Case in a healthcare worker in a maternity ward or newborn nursery
Education
Public health personnel should manage the distribution of information to contacts
(usually in the form of a letter and fact sheet) through the treating doctor, or if required,
directly or via the case or other intermediary (e.g., director of the childcare centre,
school principals, hospital infection control staff, etc). Contacts should be advised that they
are infectious as soon as they develop catarrhal symptoms and should be excluded
(immediately) from child care, preschool, school, healthcare and workplace settings and
seek early medical assessment.
Isolation and restriction For childcare and healthcare settings, refer to the Exclusion section of Table 2.
The general principles are to recommend exclusion of unvaccinated or incompletely
vaccinated contacts (as outlined in Table 2) until:
the expiry of 14 days from their first exposure to the infectious case, or
they have completed 5 days of a course of an appropriate antibiotic.
The period of exclusion for 14 days from first exposure considers the highly (but waning)
infectious nature of pertussis and covers the usual length of an incubation period (7-10
days). The benefit of exclusion is to a) protect the child contact who has not received 3
effective doses of vaccine and therefore is not protected against disease and b) reduce the
risk of transmission from the child contact to any other person in the setting who is at
increased risk of severe and/or complicated disease. If parents do not follow an exclusion
request despite public health personnel attempting to convince them of the need to do
so, then specific jurisdictional public health legislative provisions, where they exist, may
need to be applied.
In hospital settings, patients with pertussis should be in respiratory isolation until they
are no longer infectious (i.e. until they have received at least 5 days of a course of an
appropriate antibiotic). Ensure staff follow droplet precautions18
(including wearing a
surgical mask) during close contact with cases.
12. Special situations
Cases among children in child care In this document child care refers to long day care, family day care or settings where
children aged 4 years or less are in care before they start their first year of school (this can be
called preschool or kindergarten in certain jurisdictions).
In addition to usual case and contact investigation, it is important to emphasise to
parents and directors of childcare facilities the need to establish each child’s immunisation
status, the importance of all children complying with the immunisation schedule and the
need to remain alert for symptoms in their child/ren. It is also important to recommend
that the facility remain alert for respiratory illness for at least an incubation period (21
days) after last contact with the infectious case and ensure appropriate management of
any further cases.
In the family day care setting where one or more infants <6 months of age are being cared
for, a case in the carer or a member of the carer’s family may warrant temporary closure,
as exclusion of the case is generally not practicable.
Cases among children in playgroup Exposures in the playgroup setting need to be considered on a case by case basis.
Considerations need to include:
the length of time spent outdoors (which is considered a lower risk exposure)
the length of exposure time
the age of the children involved.
Cases among children in kindergarten/preschool or school If advice is sought from the Public Health Unit in these situations, it is important to
emphasise to parents and principals/directors of these facilities the need to establish
each child’s immunisation status, the importance of all children complying with the
immunisation schedule and the need to remain alert for symptoms in their child/ren. It is also
important to recommend that the facility remain alert for respiratory illness for at least one
incubation period (21 days) after last contact with the infectious case, that the facility report
cases of respiratory illness and ensure appropriate management of any further cases.
Case in a healthcare worker in a maternity ward or newborn nursery For probable or confirmed cases, consult immediately with facility management and staff
from infection control or staff health to institute a management plan appropriate to the
facility. This should include procedures to:
Confirm the diagnosis through expert clinical review and laboratory testing(ideally
by PCR). Concurrent investigation of alternative diagnoses (e.g. Mycoplasma
pneumoniae, Chlamydophila pneumoniae, viral (such as adenovirus,
metapneumovirus, parainfluenza, influenza A and B, rhinovirus, RSV), and non-
infectious causes) will assist in interpretation of equivocal or indeterminate
serological results or where there may be co-infection.
Carry out active surveillance for pertussis among exposed patients, staff,
students, volunteers and visitors.
Staff members, students and volunteers detected through active surveillance with symptoms suggestive of pertussis should be immediately excluded and requested to undergo prompt medical evaluation.
Manage cases appropriately. See section 9 Case management.
Define and identify contacts for prophylaxis and exclusion. Refer to list of high risk
contacts (see contact definition in Section 11) and recommendations in Table 2.
Review staff health records to ensure that all have been protected in line with current immunisation recommendations.
Cases who are pregnant Pertussis infection early in pregnancy may provide subsequent protective antibodies to a
neonate. As the timing of delivery is not predictable, a pregnant woman with pertussis onset
within a month of expected delivery and her household contacts should receive antibiotic
therapy22
as recommended in Table 1. If the baby is born before the mother or household
contacts have completed 5 days of a course of appropriate antibiotic treatment, then the baby
should receive antibiotic prophylaxis.
Outbreaks When outbreaks of pertussis are identified, additional control measures should be
considered. An outbreak is defined as two or more cases which share a plausible
epidemiological link e.g. clustered in time and place (such as in the same room, ward or
similar confined setting where transmission is suspected to have occurred in that setting).
An outbreak case definition of a cough illness lasting >14 days may be used to count cases, if
one case has been laboratory confirmed. Depending on the people affected and nature of
the setting, control strategies may also include:
active case finding
epidemiological studies to determine risks for infection
alerts to doctors in the community
media alerts to the wider community
cocooning vaccination initiatives
other measures as appropriate, including community-wide promotion of
vaccination.
If an outbreak occurs in a healthcare facility, an outbreak management team should be
convened, including a senior facility manager, Public Health Unit staff if appropriate, an
infection control practitioner and appropriate clinical staff.
13. References 1. Centers for Disease Control and Prevention. Epidemiology and Prevention of
Vaccine-Preventable Diseases, The Pink Book. 12th edn: National Center for
Immunization and Respiratory Diseases, Centers for Disease Control and Prevention;
April 2011.
2. Heymann DL, editor. Control of communicable diseases manual. 19th edn.
Baltimore: United Book Press; 2008.
3. Warfel JM, Beren J, Merkel TJ. Airborne transmission of Bordetella
pertussis. J Infect Dis 2012;206(6):902-906.
4. Waters V, Halperin S. Bordetella pertussis. In: Mandell GL, Bennett JE,
Dolin R, editors. Principles and practice of infectious diseases. 7th edn.
Philadelphia: Churchill Livingstone; 2010.
5. NNDSS Annual Report Writing Group, Sloan-Gardner T, Stirzaker S, Knuckey
D, Pennington K, Knope K, et al. Australia's notifiable disease status,
2009: annual report of the National Notifiable Diseases Surveillance System.
Commun Dis Intell 2011;35(2):61-131.
6. NNDSS Annual Report Writing Group. Australia's notifiable disease status,
2010: annual report of the National Notifiable Diseases Surveillance System. In:
unpublished data.
7. World Health Organization. Pertussis. 2010. Accessed on 16 Mar. Available from:
http://www.who.int/immunization_monitoring/diseases/pertussis/en/
8. National Centre for Immunisation Research and Surveillance of Vaccine
Preventable Diseases. Vaccine Preventable Diseass in Australia, 2005 to 2007.
Commun Dis Intell 2010;34(Suppl ):S1-S167.
9. Australian Technical Advisory Group on Immunisation Australian
Government Department of Health and Ageing. ATAGI Bulletin 41st Meeting: 15-
16 October 2009. In. Canberra; 2009.
10. Australian Technical Advisory Group on Immunisation Australian
Government Department of Health and Ageing. ATAGI Bulletin 44th Meeting: 24-
25 February 2011. In. Canberra; 2011.
11. Wendelboe AM, Van Rie A, Salmaso S, Englund JA. Duration of immunity
against pertussis after natural infection or vaccination. Pediatr Infect Dis J
2005;24(5 Suppl):S58-S61.
12. National Center for Immunization and Respiratory Diseases Division of
Bacterial Diseases. Best Practices for Health Care Professionals on the use of
Polymerase Chain Reaction (PCR) for Diagnosing Pertussis 2011. Accessed on 2
Mar. Available from: http://www.cdc.gov/pertussis/clinical/diagnostic-
testing/diagnosis-pcr-bestpractices.html
13. World Health Organization. Pertussis vaccines: WHO position paper. Wkly
Epidemiol Rec 2010;85(40):385-400.
14. Centers for Disease Control and Prevention. Recommended Antimicrobial
Agents for the Treatment and Postexposure Prophylaxis of Pertussis. MMWR
Recommendations and Reports 2005;54(No. RR-14).
15. Altunaiji S, Kukuruzovic R, Curtis N, Massie J. Antibiotics for whooping cough
(pertussis). Cochrane Database Of Systematic Reviews (Online)
2007(3):CD004404.
16. Antibiotic Expert Group. Therpaeutic guidelines: antibiotic. Version 14.
Melbourne: Therapeutic Guidelines Limited; 2010.
17. Kucers A, Crowe SM, Grayson ML, Hoy JF. The use of antibiotics: A clinical
view of antibacterial, antifungal, and antiviral drugs. 5th edn. Oxford:
Butterworth-Heinemann; 1997.
18. National Health and Medical Research Council. Australian Guidelines for the
Prevention and Control of Infection in Healthcare. Canberra: Australian
Government; 2010.
19. Edwards KM, Decker MD. Pertussis vaccines. In: Plotkin S, Orenstein W, Offit
P, editors. Vaccines. Fifth edn. China: Elsevier; 2008.
20. Dodhia H, Miller E. Review of the evidence for the use of erythromycin in the
mangement of persons exposed to pertussis. Epidemiol Infect 1998;120:143-
149.
21. Manikkavasagan G. and the Pertussis Guidelines Group. Health Protection
Agency Guidelines for the public health management of pertussis. London; 2010.
22. Centers for Disease Control and Prevention. Prevention of Pertussis,
Tetanus, and Diphtheria among Pregnant and Postpartum women and their
infants. MMWR Recommendations and Reports 2008;57(No. RR-4).
14. Appendices
14. Appendices
PHU checklist
Pertussis investigation form
Factsheet
Sample letter to parents of a child in a childcare facility with pertussis
Fax back form for preventing pertussis in high risk groups
